mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: "Jan Beulich" <JBeulich@suse.com>
To: <mingo@elte.hu>, <tglx@linutronix.de>, <hpa@zytor.com>
Cc: <luto@kernel.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH] ix86: really make user_mode() work correctly for VM86 mode
Date: Thu, 28 May 2015 09:16:45 +0100	[thread overview]
Message-ID: <5566EB0D020000780007E655@mail.emea.novell.com> (raw)

While commit efa7045103 ("x86/asm/entry: Make user_mode() work
correctly if regs came from VM86 mode") claims that "user_mode() is now
identical to user_mode_vm()", this wasn't actually the case - no prior
commit made it so.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Andy Lutomirski <luto@kernel.org>
---
 arch/x86/include/asm/ptrace.h |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- 4.1-rc5/arch/x86/include/asm/ptrace.h
+++ 4.1-rc5-ix86-user_mode/arch/x86/include/asm/ptrace.h
@@ -107,7 +107,8 @@ static inline unsigned long regs_return_
 static inline int user_mode(struct pt_regs *regs)
 {
 #ifdef CONFIG_X86_32
-	return (regs->cs & SEGMENT_RPL_MASK) == USER_RPL;
+	return ((regs->cs & SEGMENT_RPL_MASK) | (regs->flags & X86_VM_MASK))
+	       >= USER_RPL;
 #else
 	return !!(regs->cs & 3);
 #endif




             reply	other threads:[~2015-05-28  8:16 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-05-28  8:16 Jan Beulich [this message]
2015-05-28 17:33 ` Andy Lutomirski
2015-05-29  7:49   ` Ingo Molnar
2015-05-29  7:51 ` [tip:x86/urgent] x86/asm/entry/32: Really " tip-bot for Jan Beulich

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=5566EB0D020000780007E655@mail.emea.novell.com \
    --to=jbeulich@suse.com \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@kernel.org \
    --cc=mingo@elte.hu \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®